Cold in and out 

Posted: 5:57 pm Sunday, October 29th, 2017

By Kirk Mellish

The weak La Nina base state to the atmosphere continues in front of us, as cold comes but can not hold.

Instead we progress back to the trough and cool west ridge and warm east pattern we’ve seen most of September and October. So temperatures here quickly begin to moderate:

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But longer term the ridge shrinks over the south as the pattern tries to shift to some weak ridging out west:

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So cooler air presses into the Northern U.S. and the unseasonably warm weather here backs off:

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This pattern of brief cool spells interrupted by above normal temperatures looks like it will largely persist for November.

Pretty dry the next 5-7 days until the next front can make it our way:

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But it may struggle to make it into the area.

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Some of the current best match analogs, while NOT the final package, and model output still suggest weak La Nina or “barely” a La Nina for the winter months.

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Such weakly cool ENSO patterns in the past have yielded an average of just over an inch of snow in Atlanta. So we will have to continue to monitor the strength of the La Nina among many other factors going forward for any changes.

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